Structure of the Scalars

Abstract

The PDG Tables list more scalar mesons than can fit into one quark model nonet: indeed, even more than can belong to two multiplets. Consequently, some of these must be states beyond the quark model. So which of these is $\bar{q}q$ or $\overline{qq}qq$ or multi-meson molecule or largely glue? How experiment can help us distinguish between these possibilities is discussed.

Comments: 12 pages, 5 figures. Invited talk at MENU 2007, 11th International Conference on Meson-Nucleon Physics and the Structure of the Proton, September 10-14, 2007, IKP, Forschungzentrum Jülich, Germany